Currently, wireless communication systems such as a mobile phone system and a wireless local area network (LAN) are widely used. In addition, in the field of wireless communication, next-generation communication technologies are being continuously discussed in order to further improve a communication speed and a communication capacity. For example, in 3rd Generation Partnership Project (3GPP) serving as a standardization body, the standardization of a communication standard such as Long Term Evolution (LTE) or LTE-Advance (LTE-A) based on the LTE has been completed or is being studied.
In recent years, it has become possible for terminal devices such as smartphones to perform wireless communication using a plurality of wireless communication methods (or wireless media) including a public line network such as a mobile phone network, a wireless local area network (LAN), and so forth. For example, the terminal device performs wireless communication using the public line network, and in a case where it is not possible to use the public line network, such as in an underground mall, it is also possible to perform wireless communication using the wireless LAN.
Also on a network side, a network called Heterogenous Network (HetNet) starts to garner attention. The HetNet is, for example, a network where cells of varied sizes, such as a macrocell, a picocell, and a microcell, are hierarchized. In the HetNet, using, for example, different wireless communication methods (the LTE and 3G or the like) or different frequency bands, wireless communication is performed. Since cells are hierarchized in the HetNet, it is possible to improve the capability (capacity) of an entire mobile communication system.
As techniques relating to such wireless communication, the following techniques are cited, for example. In other words, there is a communication control device adjusting the degree of congestion in a base station responding to each wireless communication method, based on the priority of a wireless communication method, given notice of by a communication terminal device, the degree of conformance calculated based on the index of each wireless communication method, and an estimated consumed resource. According to this technique, for example, a multimode terminal compatible with a plurality of wireless access methods is able to be adjusted so that a load is not concentrated on a base station of a specific access method.
In addition, there is also a wireless device that distributes packets with respect to three links accessing a base station using IEEE802.11a, IEEE802.11b, and IEEE802.11g so that the average delay times of the three links become even, and transmits the packets to the base station. According to this technique, for example, it is possible to improve a communication efficiency in a cognitive wireless network.
Furthermore, there is also a technique where a wireless communication device selects at least one wireless module different from one another, based on an estimated transmission rate and the estimated power consumption amount of a battery, the wireless communication device being applied to a heterogenous wireless communication system performing wireless communication using simultaneously various types of wireless communication method. According to this technique, for example, it is possible to efficiently utilize the battery of a terminal.
Furthermore, there is also a technique where, in a wireless base station including a plurality of wireless media such as a wireless LAN and Worldwide interoperability for Microwave Access (WiMAX), the distribution ratio of transmission frames is determined based on wireless information such as a received signal strength indicator (RSSI) acquired from each wireless module or a data amount waiting to be transmitted.
Techniques of the related art have been disclosed in Japanese Laid-open Patent Publication No. 2012-134817, Japanese Laid-open Patent Publication No. 2010-109824, Japanese Laid-open Patent Publication No. 2012-15793, and Japanese Laid-open Patent Publication No. 2008-85759.